Along with the rapid development of the display technology, touch panel has been widely used in our lives. Currently, depending on its structure, the touch panel may include an add-on touch panel, an on-cell touch panel, and an in-cell touch panel. For the add-on touch panel, it is manufactured independently of a liquid crystal display (LCD), and then they are adhered together to form the LCD with a touch function, so the add-on touch panel has such drawbacks as high manufacture cost, low light transmittance and a thick module. For the in-cell touch panel, its touch electrodes are built in the liquid crystal display, so as to reduce a thickness of the entire module as well as the manufacture cost of the touch panel, thus it has been favored by the manufacturers.
An existing capacitive in-cell touch panel includes a mutual-capacitive touch panel and a self-capacitive touch panel. For the mutual-capacitive touch panel, a plurality of driving electrodes (Tx) and a plurality of sensing electrodes (Rx) are arranged in a crisscross manner in the touch panel, and capacitance is formed at a location where the driving electrode and the sensing electrode in different layers cross each other. A driving signal TX is applied to the driving electrodes in a scanning manner, and a corresponding sensing signal is generated by the sensing electrodes. When a touch has been made, a human body or a stylus gets close to a touch region, so as to affect the capacitance between the electrodes at this region and lead to a change in the sensing signal generated by the sensing electrode, thereby it is able to determine a touch position. For the self-capacitive touch panel, the driving electrode (Tx) and the sensing electrode (Rx) are an identical electrode, i.e., a touch electrode. The driving signal TX may be applied to the touch electrode, and the touch electrode may receive a feedback signal by itself. When no touch is made by a finger, a capacitance of the touch electrode is of a constant value A, and when the touch is made by the finger, the capacitance of the touch electrode is a sum of a finger capacitance and the initial capacitance A. Different sensing signals are generated depending on different capacitances, so it is able to determine a touch position.
In order to prevent the display from being adversely affected by the electrodes, generally the driving electrodes and the sensing electrodes are made of a transparent conductive material, e.g., indium tin oxide (ITO). For the self-capacitive touch panel, each touch electrode is connected to a driver circuit/detection circuit via a driving signal transmission line. In order to ensure a touch effect, the driving signal transmission line is made of a low-resistance metal material. The touch electrode and the driving signal transmission line are arranged at different layers, so the touch electrode is connected to the driving signal transmission line through a via-hole. As shown in FIG. 1, taking a condition where thee touch electrodes 1 are arranged in one column as an example, the driving signal transmission line 2 is connected to the corresponding touch electrode 1. In order to reduce the resistance of the touch electrode 1, a plurality of via-holes 3 is arranged at a region where the touch electrodes 1 are located, and the via-holes 3 are connected to each other via a conductive connection line 4.
In order to prevent the driving signal transmission line 2 from being connected to the touch electrodes other than the corresponding touch electrode 1, no via-hole is provided at a position corresponding to the driving signal transmission line 3 at a region where the touch electrodes other than the corresponding touch electrode Tare located. As shown in FIG. 1, a minimum of via-holes 3 are arranged at an undermost region where the touch electrode is located. In other words, the via-holes are distributed irregularly at the regions where different touch electrodes are located, which thus results in differences between pixels, e.g., different aperture ratios, different light diffraction efficiencies, and different electric fields. As a result, uneven display of the display panel will occur and a resultant display effect will be adversely affected.